An example of a disk drive apparatus for recording or/and replaying a still video signal has been disclosed in the Japanese published unexamined patent application with laid-open No. 57677/1983. This disk drive apparatus provides a structure that a cassette holder is pivotally supported at its one end with capability of swaying to a fitting substrate providing a rotating base and after a magnetic sheet jacket (hereinafter referred to as a disk cartridge) is inserted into said cassette holder, said holder is rotated to the side of fitting substrate, loading the disk cartridge on the rotating base. During the loading, as indicated in FIG. 18, a regulating plate 119 which regulates height of information recording medium 120 (hereinafter referred to as a disk) for a magnetic head 158 enters the disk cartridge 121, regulating a clearance between the magnetic head and disk 120 and giving a predetermined loading pressure. This regulating plate 119 is adustably provided in the side of a lid (case cover 118 in the prior art), and the holder is pivotally supported by said case cover 118 with capability of a certain swaying. Therefore, when the case cover 118 is opened, the holder is a little separated from the case cover 118 and said regulating plate 119 is located at the outside of case of disk cartridge 121. Thereby, when the case cover 118 is opened, the disk cartridge 121 can be freely inserted or removed.
Said disk drive apparatus is called a top-loading system wherein the opening and closing operations of the lid (case cover 118 in above example) provided with the holder of disk cartridge correspond to the eject operation and loading operation of disk cartridge. In case the front loading system is employed considering operationability and space factor, it is necessary that the regulating plate 119 is capable of going into or back from the holder in accordance with loading or unloading of disk cartridge 121. As the going and returning operations of this regulating plate 119, combination of caridge and hold case rotatably supported by the end part of cartridge, for example, which is widely employed for the drive apparatus of flexible magnetic disk, is known. In this combination, however, the coupling part of cartridge and hold case is protruded to the side portion of holder and the space, in which said coupling part can move as much as the stroke for at least the magnetic head to move in the recording region, is required, resulting in the limit for reduction in size.
In order to complete this problem, a front loading type disk drive apparatus has been proposed by the Japanese utility model application No. 036317/1985.
This disk, as indicated in FIG. 7 to FIG. 17, mainly comprises a frame 1, a slide plate 2 which can slide in the vertical direction of FIG. 7 at the upper surface of frame 1, a cartridge holder (hereinafter called a holder) 7 which is provided with projections 6a, 6b engaging respectively with the cam grooves 5a, 5b formed at the side plates 24, 25 of the slide plate 2 adjacent to the side plates 3, 4 of frame 1 respectively at the side surfaces and holds the disk cartridge 50, a motor 9 which is provided at the upper surface of frame 1, rotates a turntable 8 and forms a disk drive mechanism with the turntable 8, a caridge 10 which is provided at the surface of frame 1 and can be transferred in the radius direction of disk, a caridge transfer mechanism 12 which transfers said caridge with a stepping motor 11, and a lock lever 14 which is provided with an operation pin 13 which is erected at the deepest part in the inserting direction of cartridge 50 and is regulating the slide position of the slide plate 2.
The frame 1 is set to the size near the external size of disk cartridge 50 by bending a metal plate material and the motor fitting part 15 is also formed thereto at the center thereof with a part lifted from the bottom plate 16. The fitting part 17 of the caridge transfer unit 29 which will be described subsequently is provided and the two fitting holes 19 of the pad adjusting pin 18 as the height adjusting means of pad 41 at the end part of cam plate 42 as the regulating member are bored to the disk cartridge inserting side B of the frame 1. Moreover, the fitting part 21 of positioning pin 20 which supports the disk cartridge 50 at the time of loading is provided at three points in total, one is in the disk cartridge inserting side B and other two are respectively in the corners opposed to the disk cartridge inserting side, and the fitting part 23 of a tensile spring 22 which always presses the slide plate 2 in the disk cartridge inserting side B is also provided.
The side plates 3, 4 are formed erecting in both sides of the frame 1, the left side plate 3 viewed from the disk cartridge inserting side B is provided with two guides grooves 26a which guide the end portions of protections 5a which will be described subsequently, while a fitting hole 28 of guide shaft is formed in the side opposed to the disk cartridge inserting side. Meanwhile, the right side plate 4 viewed from the disk cartridge inserting side B is provided with the guide 26 which is the same as that described above and allows insertion of the projection 32 of a bearing 31 of screw shaft of the caridge transfer unit 29.
A recessed part 33 is formed at the bottom part of the slide plate 2, and this recessed part 33 is located at the lower surface of motor fitting part 15 of said bottom plate 16 and slides within the range of said fitting part 15. The side plates 24, 25 are respectively provided with the cam grooves 5a, 5b to which projections 6a, 6b projected in the side of the holder 7 are inserted. In addition, the cam surface 43 of the reciprocal cam which causes the cam plate 42 to go up and down and is provided as the regulating member which is described later and provides a pad 41 is formed in the side opposed to the disk cartridge inserting side of the right side plate B viewed from the disk cartridge nesting side B. The large and small openings shown in FIG. 10 are respectively an insertion hole 44 to which the guide shaft 27 is inserted and an engaging hole 45 with which the end face of lock lever 32 engages, and said eject lever 31 is fitted to the fitting hole 46 formed in the same side.
As shown in FIG. 15, the holder 7 is provided with an insertion hole 47 of disk cartridge 50 at the lower side.
The left side surface of holder 7 is provided with two projections 6a, an elastic segment 48 is integrally extended in perpendicular from the right side surface and the end face of this elastic segment 48 is provided with a projection 6b. These projections 6a, 6b move along the cam grooves 5a, 5b in the embodiment of the present invention and therefore the drive rollers 49a, 49b are respectively provided rotatably at the inner side. The latest end of the holder viewed from the disk cartridge insertion port 47 is provided with a stopper 51 which regulates the inserting position of the disk cartridge 50. The main table side 8 of holder 7 is opened almost entirely and the support segment 53 formed at the lower side of said side surface supports the disk cartridge 50.
As shown in FIG. 7, the caridge 10 has a turntable insertion hole 52 to which the turntable 8 is rotatably inserted, a bearing 54 of a long span is loaded to the upper part thereof and metals are respectively set with both ends of said bearing 54.
The lower part of caridge 10 is pressurized in contact with the screw shaft 30 of caridge transfer mechanism 12 from the holder side 7 and is also provided with a contact segment 55 which regulates the height of caridge 10.
The caridge transfer unit 33 provided as the caridge transfer mechanism mainly comprises a support plate 56, a stepping motor 11 and a screw shaft 30. The support plate 56 is bent in two stages as is apparent from FIG. 8 and the stepping motor 11 is provided between said support plate 56 and the bottom plate 16.
An intermittent drive screw 57 engraved to the screw shaft 30 is set so that the axial running pitch in accordance with a range of preset rotating angle corresponds to the width of recording track of disk. Moreover, this screw shaft 30 is set with a stopper 58 and a flat gear 59. The stopper 58 regulates rotation of the screw shaft 30 with the protruded portion thereof engaged with the projection of said contact segment 55, thereby rejecting transfer of caridge 10. The stop position corresponds to the track position of magnetic head 59.
The flat gear 59 set to the screw shaft 30 engages with a crown gear 60 set to the rotating shaft of the stepping motor 11. The step operation of stepping motor 11 is transmitted to the screw shaft 30 via the crown gear 60 and flat gear 58. Thereby, rotating operation of stepping motor 11 is transmitted to the caridge 10 via said intermittent drive screw 57 in order to make the caridge 10 advance in straight in each step.
A pad adjusting pin 18 is erected as an adjusting means and the end part thereof is protruded from the pad insertion port of holder 7 in the disk cartridge insertion side B in such a degree as regulating the height of pad 41 provided to the end part of cam plate 42 described later for the magnetic head. The pad 41 regulates relative height of the disk and magnetic head 80 by regulating the height for the magnetic head 80. The pad adjusting pin 18 is mainly composed, as shown in FIG. 11, of a support pin 83 forming a through hole 82 at the lower part of center, an adjusting pin 86 where the female screw 84 is cut at the lower part of center and the contact part 85 is formed at the upper part, and an adjusting screw 87 which is inserted from the lower end of the through hole 82 of support pin 83 and engages with the female screw 84 of said adjusting pin 86. A spring washer 88 is inserted as an elastic member between the adjusting pin 86 and the support pin 83 and fine adjustment is possible within the range where an elastic force of spring washer 88 is effective by rotating the adjusting screw 87. Therefore, a collar 89 is formed to the adjusting pin 86 and said through hole 82 of the support pin 83 is provided with a stepped portion 83a with which the head adjusting screw 87 is pressurized in contact.
This pad adjusting pin 18 is inserted to a fitting hole 19 from the upper surface of bottom plate 16 and is fitted by caulking the lower end of support pin 83 to the outside.
The cam plate 41 is provided with a pad 42 in the side of end part and at the upper part thereof, a roller 64 which rotatably moves on the cam surface 43 of the reciprocal cam formed to the side plate 29 of slide plate 2 is projected at the lower end of the side plate 65 extended perpendicularly and said pad 42 and roller 4 form a device having the function as the cam follower. In addition, a positioning hole 41a is bored to the area of pad 42 opposed to said pad adjusting pin 18 and said contact part 85 engages with said hole during the loading of holder, thereby regulating the height of pad 42 for the magnetic head 59. During the unloading of holder 7, this cam plate 41 goes back from the case of holder 7 as shown in FIG. 15 with the pad 4 located at the upper part of holder 7. During the loading of holder 7, the cam plate 41 is located within the holder 7, pressing the disk surface. Thereby, the cam plate functions as a regulating member.
The caridge transfer unit 33 is fitted to the unit fitting hole 66 of bottom plate 16 by screwing. In this case, the protruded part 32 of bearing 31 is inserted into the fitting hole of side plate 4 of frame 1 and the bearing 31 is fixed to the frame 1 at the three points in total of said fitting hole and two unit fitting holes 66.
The caridge 10 is supported between the guide shaft fixed between both side plates 3, 4 and screw shaft 30 of caridge transfer unit 33 and thereby reciprocally moves to the right and left, owing to the structure described above.
The positioning pin 20 provides a placing part 67 and inserting part 68. Said inserting part 68 is inserted to the positioning pin inserting port formed to the case of said disk cartridge 50, and the lower surface of case is placed in contact with said placing part 67 for the positioning of case.
The loading operation of disk drive apparatus constituted as explained above will then be described subsequently.
Before the disk cartridge 50 is inserted to the holder 7, the holder 7 is located furthest from the turntable 8, for example, as shown in FIG. 15 and FIG. 16 and in this case projections 6a, 6b of holder 7 are respectively located at the highest part of guide grooves 26a, 26b and are also located at the horizontal part at the upper end of cam grooves. Under this condition, the projection 69 of the lock lever 14 engages with the edge of engaging hole 45 of the slide plate 2, holding the slide plate 2 in the deepest position for the disk cartridge inserting side B.
When the disk cartridge 50 is inserted into the holder 7 from said waiting condition, the end part of case is placed in contact with an operation pin 13 of the lock lever 14. When it is further inserted, the lock lever 14 rotates counterclockwise as shown in FIG. 13, resetting the engagement between the projection 69 and the edge of engaging hole 45 of the slide plate 2. In this timing, the slide plate 2 slides to the disk cartridge inserting side B with an elastic force of the tensile spring 22 which is always activated in said disk cartridge inserting side B. Thereby, as shown in FIG. 14 and FIG. 17, the rollers 56a, 56b of the projections 6a, 6b are displaced along the cam grooves 5a, 5b and the projections 6a, 6b are inserted to the guide grooves 26a, 26b of frame 1. Therefore, displacement by the cam grooves 5a, 5b is converted to the movement perpendicular to the direction of turntable 8. The drop position of disk cartridge 50 is regulated by the height of placing part 67 of said positioning pin 20 and the case can no longer drop exceeding such drop position. During this downward movement, when the shaft inserting hole 51 of a hub 51c of disk cartridge 50 is engaged with said fixed shaft (spindle shaft) 70 and is located to the lowest position, it is certainly engaged with pressure to the rotating part inserted with said fixed shaft 70.
With such loading operation, said roller 64 moves along the cam surface 43 and the pad 42 is located within the holder 7, and finally the cam plate 41 is pressurized in contact with the disk surface and necessary loading pressure can be obtained by a plate spring 71 provided separately.
Next eject operations are explained hereinafter.
When the disk is loaded as explained above and recording or replay is completed, the disk is protruded from an opening 29 of side plate 3 of the frame 1, and the eject lever 31 which is located in the disk cartridge inserting side B is slid in the side opposed to the disk cartridge inserting side, namely in the direction of arrow mark H of FIG. 13. Such sliding operation causes the slide plate 2 to return in the H direction. When said engaging hole 45 bored to the slide plate 2 is located to the position corresponding to the projection 69 of lock lever 14, the lock lever 14 rotates clockwise with an elastic force of the spring 81 and engages wit the edge of hole 45 from the projection 69. During this operation, the holder 7 rises along said cam holes 5a, 5b and the hub 51c of disk separates from the turntable 8. When the lock lever 14 rotates as explained, the operation pin 13 exhausts the end part of case in the disk cartridge inserting side B with an elastic force of the spring 81. During this process, the cam plate 41 rotates counterclockwise up to the position indicated in FIG. 15 from the position of FIG. 14, since the roller 64 rises along the cam surface 43 and the pad 42 separates from the disk surface and returns to the upper surface of holder 7, eject operation can be carried out smoothly. This returning operation makes free the loading and unloading of the disk cartridge 50.
However, the conventional disk drive apparatus realizes reduction in size by employing the front loading system but does not result in good positional relation between the head surface and recording medium because the contact condition between the head surface and recording medium surface is uniquely determined by the pressing condition of the pad 42.